The purpose of this study is to determine the concentration of the antibiotic Grepafloxacin (Raxar) or Ciprofloxacin (Cipro) in the lung after taking a single dose. Both drugs are used for treating lung infections such as pneumonia and acute exacerbations of chronic bronchitis caused by bacteria that are resistant to many antibiotics. The greater the amount of antibiotic that is deposited at the site of the infection, the faster the bacteria is eliminated and the course of treatment is shorter.